Design optimization of oxygenated fluid pump

Abstract

In medical emergencies, an oxygen-starved brain quickly suffers irreparable damage. In many cases, patients who stop breathing can be resuscitated but suffer from brain damage. Dr. John Kheir from Boston Children's Hospital created a compressible fluid that can re-oxygenate blood quickly in patients with asphyxia and cardiac arrest. Because the fluid is compressible, the set infusion rate on an ordinary pump does not necessarily indicate what is delivered. In addition, the fluid is provided at a 90% gas by volume concentration and is extremely viscous. The goal of this project is to create a pump to deliver a specified volumetric flow rate of the oxygenated fluid created by the doctor. The pump design uses a bellows with force feedback calibration to pump 1 liter of fluid over 5 minutes and mix the concentrated 90% form with saline without degradation to form a 70% concentrated form with the viscosity similar to that of blood. My part in the project was to create the control system that would drive the pump using a force feedback and to optimize the design of the pump The oxygenated fluid pump built can successfully store and dispense one liter of fluid, mix the concentrated form of the oxygenated fluid with saline, maintain sterility, and preserve the fluid's properties, all in a cost appropriate manner. It is a modular design that can easily be modified to improve its performance. Further testing is required to tune the control system and ensure that the flow rate is accurate to ±10%. The pump is mostly being used as a research tool in order to run tests that will help characterize the fluid and later can be used for small and large animal testing.